Pumping device in particular for volatile liquids



March 7, 1939. P. A. GUINARD PUMPING DEVICE IN PARTICULAR FOR VOLATILE LIQUIDS Filed Jan; 28 1957 Patented Mar. 7, 1939 PUMPING ,EVIGE IN ran-momma FOR om'rma mourns run Andre Guinard,- Saint-Cloud, France iipplication January as, 1937, Serial No. 122,745 In France January 31, 1936 1 Claim. (cl. 103-45 The present invention relates to a pumping de- 7 vice particularly applicable .to volatile liquids,

such as gasoline,- stored in underground reservoirs, the bottom of which may be below the level of the ground at a considerable depth which can attain to meters-for large'reservoirs. in this case, if it is des'iredjo draw oh the gasoline containedfin such reservoirs by means of a pump, it is necessary to effect very considerable earth: works and masonry to arrange the pump at less than 4 meters above theebottdm of tlie reservoir; effectively, for a suction height which is greater than Ameters, the depression produced by the pump causes the gasoline to evaporate and the 5 pump only sucks up 'vapour, so that by arranging the pump at a greater distance from the bottom of the reservoir, the latter cannot be emptied c under; satisfactory working conliitions. Fathermore, the conditions operation of such an installation are not'sa factory: when the level of the gasoline in the reservoir is low, for example when the suction height of the pump'exceeds 2 meters, the evaporation begins to become "considerable and the pump sucks up a mixture of 0 liquid and vapour which produces extremely violent vibrations in the delivery pipe which are capable of destroying the welds between the suc- 'tion pipe and the reservoir and of thereby causa hydraulic generator I actuated by a motor 8,

'ing flooding. r 3 Y I The device which is the object of the present invention is intended to overcome these drawbacks and it is characterized by the fact that it comprises a motor-pump unit immersed in the reservoir adjacent thebottom of the, latter, and

of which the pump, which is preferably of the centrifugal type, is directly coupled to ahydraulicq motor actuated byda. fluid which is not miscible density "is greater than that oi the latter, for 40 example; in the case of a reservoir for gasoline,

' castor oil or glycerlne.

I Byway of example, an embodiment of thedevice according to the invention has been deea lier the foll'qwing reasonsi 1 1 with the liquid to be pumped and of which the scribed hereinafter and; illustrated in the acmersed in reservoirs to be emptied and which Owing to the,,dlfliculty in making the immersed machines perfectly liquid-tight, leakages of the "actuating pressure-fluid occur infthe reservoir and afiectjahe purity of the liquid pumped,'particularly in thegase of considerable leakage. On the other hand, this same lack of liquid-tightness causes inlets of gasoline to occur in the casing of the hydraulic motor, particularly during the in-;,- operative periods when the actutlng fluid is not under pressure, said inlets of gasoline on the one handpreventing'a satisfactory lubrication of the motor, which may cause seizing, and on the other hand modifying the actuating fluid which is used in closed-circuit and which it be- I comes necessary to renew frequently.

The combination according to the present invention, of a pump immersed inthe gasoline, with a motor actuated by a fluid which is not miscible with gasoline and is heavier than the latter, enables the problem to be completely m I v the underground gasoline reservoir (Figure 1) at the bottom of which is the pumping unit 7 comprising a hydraulic motor 2 and the pump 3 arranged above a sump 4 provided in the bottom of the reservoir. The motor 2 is provided with an inlet pipe 5 and an outlet pipe 6 for the actuating fluid, of which the circulation is ensured by the niachines'being arranged for example in a likewise underground room 9. The immersed pump 3 forces the gasoline into the pipe l0. It will immediately be seen that the pump 3 always has a head whatever-be the level of the reservoir, so that it does not have to suck the 5 gasoline but only to deliver it into the pipe l0, and that all the drawbacks due tq'the evaporation of the gasoline are therefore eliminated. As the pumpdoes not have tosuck, a-centrifugal pumpgc'an be used (Figure '2) of which the rotor 40 II is keyed on the shaft l2 carrying the rotor ill of the-hydraulic motor, for example a piston rotor, whereas the stator 3 of the pump is secured to;the stator 2 of the motor. Between the two'stators is interposed a chamber H which 15 5 filled with oil and which isseparated from the said stators, by the stufllng'and-boxes l5, l6, thrpugh which the shaftl l 2 of the unit passes. aid shaft is supported by'ball bearings l1, l1 lodged in the stator 2' of the hydraulic motor, and the'rotor H of the pump, which is suspended on the end of the shaft l2, ,has no surface offriotion with the stator 3, so that the gasoline which entirely the pump cannot cause any seizlng' of the latter.

The advantages 0! this device can be explained in the following manner:

As the height of the column of gasoline con-- tained' in the delivery pipe I0 is substantially equal" to that of the column of actuating fluid contained in the pipes 5 and 6, but as the density of the actuating fluid is greater than that of the gasoline,.the pressure which .is exerted on the actuating fluid side of the stufling box IE is greater, even when the pump is inoperative, than that which is exerted on said stufling box on the gasoline side,so that if there is defective liquid tightness, it is the actuating fluid which passes into the gasoline when the pump is inoperative, and as said fluid is not miscible with gasoline and is heavier than same, it falls to the bottom of the sump 4, so that such leakages entail practically no drawback. With regard to the leakages which normally occur during the operation of the unit, their volume is' negligible as compared with the volume of gasoline delivered by the pump (for example 50 m. per hour), so that even if a portion of such leakagesis carried along with the gasoline, the latter is only rendered impure to a quitevinsigniflcant extent.

In the case in which the height of delivery of the gasoline is greater than the maximum height of the actuating jiuid above the pump, for example [when the end of the delivery pipe I0 is located above the ground as shown in Figure 1, the

To avoid this danger, the device according to the invention furthermore includes means for maintaining, when inoperative, the actuating fluid under 9. suflicient pressure to prevent the gasoline leakage indicator, a considerable drop in said level giving warning of the existence of adangerous leakage of the actuating fluid. Of course, the air bell l8 can be replaced, without exceed- I ing the scope oi the invention, by, any other pneumatic or hydraulic recuperating device. I claimf Pumping device, in particular for volatile liquids such as gasoline or the like stored in underground reservoirs, comprising a motor-pump unit which is immersed adjacent the bottom of the reservoir and which consists bf ,a rotary pump and a hydraulic motor directly coupled to said pump,

a motor-pump supply unit which is arranged outside the reservoir and of which the pump is connected to the hydraulic motor 01' the immersed unit-by a closed circuit comprising a supply pipe and a return pipe, in said circuit a liquid which is not miscible with the liquid to be pumped and which is 01 greater density than the latter, an air bell, an air compressor driven by the motor of the supply unit, and means for connecting said air bell on the one hand to the return pipe of the closed supply circuit, and on the other hand to said compressor.

PAUL ANDRE GUINARD. 

